Methods for living guidelines: early guidance based on practical experience. Paper 5: decisions on methods for evidence synthesis and recommendation development for living guidelines

Producing living guidelines requires making important decisions about methods for evidence identification, appraisal and integration to allow the living mode to function. Clarifying what these decisions are and the trade-offs between options is necessary. This paper provides Living Guideline developers with a framework to enable them to choose the most suitable model for their living guideline topic, question or context.We developed this guidance through an iterative process informed by interviews, feedback and a consensus process with an international group of Living Guideline developers.Several key decisions need to be made both before commencing and throughout the continual process of Living Guideline development and maintenance. These include deciding what approach is taken to the systematic review process; decisions about methods to be applied for the evidence appraisal process, including the use of unpublished data; and selection of "triggers" to incorporate new studies into Living Guideline recommendations. In each case, there are multiple options and trade-offs.We identify trade-offs and important decisions to be considered throughout the Living Guideline development process. The most appropriate, and most sustainable, mode of development and updating will be dependent on the choices made in each of these areas.